1. Technical Field
The present invention relates to nail guns, and more particularly, to a nail gun with a rapidly attachable and detachable magazine assembly, which is provided with a quick joining mechanism so that a user can rapidly assemble the magazine assembly to or detach the magazine assembly from the nail gun simply by a single action.
2. Description of Related Art
As a kind of tool indispensable to decoration workers, a nail gun has a magazine for accommodating a strip of nails. Conventionally, the magazine is mostly bolted to a handle portion of the nail gun, and a top portion of the magazine engages with a nosepiece of the nail gun to guide nails from the strip of nails into the nosepiece one by one so as to be further driven through the nosepiece. A conventional nail gun device disclosed in U.S. Pat. No. 6,431,429 is just representative of conventional nail gun devices. Referring to FIGS. 1A and 1B together, side views of a conventional nail gun device are illustrated therein. The conventional nail gun device 1b includes a nail gun 11b, a nosepiece 13b and a magazine 14b. A handle portion 12b of the nail gun 1b is provided thereon with a first joining mechanism 121b, which has a first joining rod 122b and a first joining hole 123b. The nosepiece 13b is provided with a second joining rod 131b thereon. The magazine 14b has a second joining mechanism 141b and a joining piece 142b. The second joining mechanism 141b is formed by a larger pressing plate 143b and a smaller pressing plate 144b in combination, and is pivoted to the magazine 14b so that the larger pressing plate 143b and the smaller pressing plate 144b can pivot upwards and downwards. Additionally, the magazine 14b further has, at a top portion thereof, a second joining hole 145b that can mate with the second joining rod 131b. 
During use of the conventional nail gun device 1b, assembling the magazine 14b to and detaching the magazine 14b from the nail gun 11b are very troublesome. Specifically, when it is desired to assemble the nail gun 11b and the magazine 14b together, one must insert the second joining rod 131b into the second joining hole 145b at first, snap-fit the joining piece 142b into the first joining hole 123b, and then pull the larger pressing plate 143b downwards so that the larger pressing plate 143b and the first joining rod 122b are snap-fitted with each other to complete the assembling process. On the other hand, when it is desired to detach the magazine 14b from the nail gun 11b, one must press the smaller pressing plate 144b at first, then pull the larger pressing plate 143b to release it from being snap-fitted with the first joining rod 122b, and finally pull the magazine 14b downwards with a force so that the joining piece 142b is pulled out of the first joining hole 123b and the second joining rod 131b is pulled out of the second joining hole 145b. 
Additionally, a device for rapid magazine detachment on a nail gun is disclosed in Taiwan Patent Application No. 096115283, an exploded view of which is illustrated in FIG. 2. The device for rapid magazine detachment on a nail gun is a combination of a nail gun 11′ and a magazine 4′. The nail gun 11′ has a handle portion 12′, a nose piece 15′ and a trigger 14′. The handle portion 12′ is provided thereon with a pivot block 13′, to which a rod 2′ is pivoted. The rod 2′ is formed with a tapered portion 21′ at an end thereof, and an elastic element (not shown) is inserted over the rod 2′ to drive the tapered portion 21′ to abut against the pivot block 13′.
Furthermore, in the device for rapid magazine detachment on a nail gun, the magazine 4′ is provided thereon with an engaging block 5′, which has an end groove 51′ and an embedding groove 52′ in communication with each other. The tapered portion 21′ of the rod 2′ is adapted to be inserted into the end groove 51′ and embedded into the bottom of the embedding groove 52′. A fastener 6′, which has an outer stopper piece 61′ and an inner stopper piece 62′, is pivoted between the engaging block 5′ and the magazine 4′. By swinging the fastener 6′ into the bottom of the embedding groove 52′, the tapered portion 21′ of the rod 2′ can be clamped by the outer stopper piece 61′ and the inner stopper piece 62′ cooperatively, with the outer stopper piece 61′ being used to block between the embedding groove 52′ and the end groove 51′. Thus, the tapered portion 21′ is restricted within the embedding groove 52′, thereby engaging the magazine 4′ with the nail gun 1′. Additionally, when it is desired to detach the magazine 4′ from the nail gun 11′, one must swing the fastener 6′ out of the bottom of the embedding groove 52′ to detach the magazine 4′. Once the magazine 4′ is detached, abnormal conditions of the nail gun 11′ such as sticking of nails can be cleared.
Additionally, other relevant nail gun products have also been provided in the market, for example, a combined nail gun as disclosed in U.S. Pat. No. 6,609,646. Referring to FIGS. 3 and 4 together, a combined nail gun as well as a top view of a snap-fit element and a snap-fit mount thereof are illustrated therein respectively. The combined nail gun, which is a conventional product currently available in the market, is a combination of a nail gun 1a and a magazine 4a. The nail gun 1a has a handle portion 12a, a nose piece 15a and a trigger 14a. The handle portion 12a is provided thereon with a snap-fit mount 13a, which has a snap-fit rod 131a and a pull lever 132a. The magazine 4a is provided thereon with a snap-fit element 5a, which has an inserting hole 51a and a slot hole 52a. A user simply needs to insert the snap-fit rod 131a into the inserting hole 51a, push it into the slot hole 52a and then press the pull lever 132a downwards in order to engage the magazine 4a with the nail gun 1a. On the other hand, when it is desired to detach the magazine 4a from the nail gun 1a, the user simply needs to pull the pull lever 132a upwards and then move the snap-fit rod 131a out of the slot hole 52a and the inserting hole 51a sequentially, thereby detaching the magazine 4a. 
The abovementioned nail guns all have the advantage of allowing the magazines to be attached to and detached from the nail guns without need of a tool. However, for the conventional nail gun device disclosed in U.S. Pat. No. 6,431,429, assembling the magazine 14b to and detaching the magazine 14b from the nail gun 11b represents a too complex procedure. For the device for rapid magazine detachment on a nail gun disclosed in Taiwan Patent Application No. 096115283, when the user swings the fastener 6′ to detach the magazine 4′, it is possible that the fastener 6′ may be excessively stuck to the bottom of the embedding groove 52′ so that the user must apply an extremely large force in order to swing the fastener 6′ out, which is a prominent defect in design; moreover, swinging the fastener 6′ back and forth frequently would cause abrasion of the fastener 6′ and the engaging block 5′ and, consequently, loose engagement of the fastener 6′, thereby causing insecure engagement of the magazine 4′ with the nail gun 11′. Finally, for the combined nail gun disclosed in U.S. Pat. No. 6,609,646, it accomplishes the purpose by snap-fitting the snap-fit rod 131a into the snap-fit element 5a and then pressing the pull lever 132a downwards to fix the snap-fit rod 131a, which design does not need a large force in attachment and detachment of the magazine 4a; however, as a plastic piece, the pull lever 132a tends to lose the ability of fixing the snap-fit rod 131a due to abrasion after repeated attachment and detachment of the magazine 4a, in which case the pull lever 132a must be replaced in order to secure the engagement of the magazine 4a with the nail gun 1a. 
Accordingly, in view of the drawbacks and shortcomings of the aforesaid conventional nail guns, the inventor of the present application has made great efforts to make inventive research thereon and eventually provided a nail gun with a rapidly attachable and detachable magazine assembly according to the present invention.